feat: empty string warning

.github/workflows/cypress-testing.yml

@@ -2,7 +2,7 @@ name: Run Cypress testing suite
 on:
   workflow_dispatch:
   pull_request:
-    types: [ opened, synchronize ]
+    types: [opened, synchronize]
 
 jobs:
   cypress-run:

.github/workflows/empty-string-warning.yml

@@ -0,0 +1,77 @@
+name: Warn for Empty Strings
+
+on:
+  pull_request:
+    paths:
+      - "**/*.ts"
+      - "**/*.tsx"
+
+permissions:
+  issues: write
+  pull-requests: write
+
+jobs:
+  check-empty-strings:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Find empty strings in TypeScript files
+        id: find_empty_strings
+        run: |
+          # Find empty strings and mark them explicitly
+          output=$(grep -Rn --include=\*.ts "''\|\"\"" --exclude-dir={node_modules,dist,out} . || true)
+
+          if [ -z "$output" ]; then
+            echo "::set-output name=results::No empty strings found."
+            exit 0
+          else
+            output=$(echo "$output" | sed 's/""/"[EMPTY STRING]"/g' | sed "s/''/'[EMPTY STRING]'/g")
+            echo "::set-output name=results::${output//$'\n'/%0A}"
+          fi
+
+      - name: findings
+        if: steps.find_empty_strings.outputs.results != 'No empty strings found.'
+        run: |
+          if [ "${{ steps.find_empty_strings.outputs.results }}" == "No empty strings found." ]; then
+            echo "No empty strings found. No action required."
+          else
+            echo "::warning::Empty strings found in the following files:"
+            echo "${{ steps.find_empty_strings.outputs.results }}"
+          fi
+
+      - name: Find Comment
+        uses: peter-evans/find-comment@v3
+        id: find_comment
+        with:
+          issue-number: ${{ github.event.pull_request.number }}
+          body-includes: Empty String Usage Detected
+          comment-author: github-actions[bot]
+
+      - name: Comment on PR
+        if: steps.find_empty_strings.outputs.results != 'No empty strings found.'
+        uses: peter-evans/create-or-update-comment@v4
+        with:
+          issue-number: ${{ github.event.pull_request.number }}
+          comment-id: ${{ steps.find_comment.outputs.comment-id }}
+          edit-mode: replace
+          body: |
+            ## Empty String Usage Detected
+
+            The following occurrences of empty strings were detected. Please review them to ensure their usage is necessary:
+
+            ```plaintext
+            ${{ steps.find_empty_strings.outputs.results }}
+            ```
+
+      - name: Remove comment
+        if: steps.find_empty_strings.outputs.results == 'No empty strings found.'
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const { owner, repo } = context.repo;
+            const { number } = context.issue;
+            const comment_id = ${{ steps.find_comment.outputs.comment-id }}
+            github.rest.issues.deleteComment({ owner, repo, comment_id });

.github/workflows/jest-testing.yml

@@ -2,7 +2,7 @@ name: Run Jest testing suite
 on:
   workflow_dispatch:
   pull_request_target:
-    types: [ opened, synchronize ]
+    types: [opened, synchronize]
 
 env:
   NODE_ENV: "test"
@@ -14,7 +14,7 @@ jobs:
     steps:
       - uses: actions/setup-node@v4
         with:
-          node-version: '20.10.0'
+          node-version: "20.10.0"
       - uses: actions/checkout@master
         with:
           fetch-depth: 0

.github/workflows/release-please.yml

@@ -20,7 +20,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v4
         with:
-          node-version: '20.10.0'
+          node-version: "20.10.0"
           registry-url: https://registry.npmjs.org/
       - run: |
           yarn install --immutable --immutable-cache --check-cache

README.md

@@ -10,18 +10,23 @@ This template repository includes support for the following:
 ## Testing
 
 ### Cypress
+
 To test with Cypress Studio UI, run
+
 ```shell
 yarn cy:open
 ```
 
 Otherwise to simply run the tests through the console, run
+
 ```shell
 yarn cy:run
 ```
 
 ### Jest
+
 To start Jest tests, run
+
 ```shell
 yarn test
 ```

tests/workflows/empty-strings/empty-strings.test.ts

@@ -0,0 +1,60 @@
+import { expect, describe, beforeEach, it } from "@jest/globals";
+import { CheckEmptyStringsOptions, checkForEmptyStringsInFiles } from "./empty-strings";
+
+const mockReadDir = jest.fn();
+const mockReadFile = jest.fn();
+
+const options: CheckEmptyStringsOptions = {
+  readDir: mockReadDir,
+  readFile: mockReadFile,
+  ignorePatterns: [],
+};
+
+describe("checkForEmptyStringsInFiles", () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it("identifies files with empty strings", async () => {
+    mockReadDir.mockResolvedValue(["file1.ts", "file2.ts"]);
+    mockReadFile.mockImplementation((path) => {
+      if (path.includes("file1.ts")) {
+        return Promise.resolve('const a = "";');
+      }
+      return Promise.resolve('const b = "notEmpty";');
+    });
+
+    const result = await checkForEmptyStringsInFiles(".", options);
+    expect(result).toEqual(["file1.ts"]);
+  });
+
+  it("ignores files based on ignorePatterns and .gitignore", async () => {
+    options.ignorePatterns = ["file2.ts"];
+    mockReadDir.mockResolvedValue(["file1.ts", "file2.ts", "file3.ts"]);
+    mockReadFile.mockImplementation((path) => {
+      if (path === ".gitignore") {
+        return Promise.resolve("file3.ts");
+      } else if (path.includes("file1.ts")) {
+        return Promise.resolve('const a = "";');
+      }
+      return Promise.resolve('const b = "notEmpty";');
+    });
+
+    const result = await checkForEmptyStringsInFiles(".", options);
+    expect(result).toEqual(["file1.ts"]);
+  });
+
+  it("returns an empty array when no empty strings are found", async () => {
+    mockReadDir.mockResolvedValue(["file1.ts"]);
+    mockReadFile.mockResolvedValue('const a = "notEmpty";');
+
+    const result = await checkForEmptyStringsInFiles(".", options);
+    expect(result).toHaveLength(0);
+  });
+
+  it("handles errors gracefully", async () => {
+    mockReadDir.mockRejectedValue(new Error("Error reading directory"));
+
+    await expect(checkForEmptyStringsInFiles(".", options)).resolves.toEqual([]);
+  });
+});

tests/workflows/empty-strings/empty-strings.ts

@@ -0,0 +1,45 @@
+export interface CheckEmptyStringsOptions {
+  readDir: (path: string) => Promise<string[]>;
+  readFile: (path: string, encoding: string) => Promise<string>;
+  ignorePatterns?: string[];
+}
+
+export async function checkForEmptyStringsInFiles(dir: string, options: CheckEmptyStringsOptions): Promise<string[]> {
+  const { readDir, readFile, ignorePatterns = [] } = options;
+  const filesWithEmptyStrings: string[] = [];
+  const ignoreList: string[] = ["^\\.\\/\\.git", "^\\.\\/\\..*", "^\\.\\/node_modules", "^\\.\\/dist", "^\\.\\/out", ".*\\.test\\.ts$", ...ignorePatterns];
+
+  try {
+    const gitignoreContent = await readFile(".gitignore", "utf8");
+    gitignoreContent.split("\n").forEach((line) => {
+      if (line.trim() !== "") {
+        ignoreList.push(`^\\.\\/${line.replace(/\./g, "\\.").replace(/\//g, "\\/")}`);
+      }
+    });
+  } catch (error) {
+    console.error("Error reading .gitignore file:", error);
+  }
+
+  try {
+    const files = await readDir(dir);
+    for (const fileName of files) {
+      let shouldIgnore = false;
+      for (const pattern of ignoreList) {
+        if (new RegExp(pattern).test(fileName)) {
+          shouldIgnore = true;
+          break;
+        }
+      }
+      if (shouldIgnore || !fileName.endsWith(".ts")) continue;
+
+      const fileContent = await readFile(`${dir}/${fileName}`, "utf8");
+      if (fileContent.includes('""') || fileContent.includes("''")) {
+        filesWithEmptyStrings.push(fileName);
+      }
+    }
+  } catch (error) {
+    console.error("Error reading directory or file contents:", error);
+  }
+
+  return filesWithEmptyStrings;
+}

tests/workflows/empty-strings/test-function.ts

@@ -0,0 +1,3 @@
+export function testFunction() {
+  return "";
+}

tests/workflows/empty-strings/test.config.ts

@@ -0,0 +1,6 @@
+module.exports = {
+  test: {
+    test: "",
+  },
+  tester: "",
+};

tsconfig.json

@@ -104,7 +104,7 @@
 
     /* Completeness */
     // "skipDefaultLibCheck": true,                      /* Skip type checking .d.ts files that are included with TypeScript. */
-    "skipLibCheck": true, /* Skip type checking all .d.ts files. */
+    "skipLibCheck": true /* Skip type checking all .d.ts files. */,
     "resolveJsonModule": true
   }
 }